Last week, The CW’s hit TV show ‘Gossip Girl’ revealed the identity of Dr. William van der Woodsen as none other than Billy Baldwin. As he geared up for his final episode, which aired yesterday at 9 p.m., he took some time out of his busy schedule to chat with Release.

Release: How did you get the part? Was it offered to you or did you have to audition for it?

Billy Baldwin: They offered me a part last season that didn’t work out because it was a one-episode guest spot. I had never seen the show before so they sent me a couple of episodes and I watched them with my wife and was totally hooked. I said, ‘Look, I love your show and I want to do it, but I just want to find something more to do than a one-episode guest spot. I’d like to come in when you have some fun, juicy arc for me to play.’ And then they came back to me with Dr. van der Woodsen.

Release: Did you get to shoot scenes with the whole cast? How was it?

BB: I worked mostly with Matthew Settle [Rufus Humphrey], Kelly Rutherford [Lily van der Woodsen], Blake Lively [Serena van der Woodsen] and Connor [Paolo] who plays my son Eric [van der Woodsen]. I did some other scenes with some of the other cast members and was on the set with them in hair and makeup. I met Leighton Meester [Blair Waldorf] a number of times and the British gentleman who plays Chuck [Bass], Ed [Westwick], I met him a couple of times.

Release: As viewers we really don’t have any prior knowledge of Serena’s father. How did you decide to play him?

BB: You talk to the writers, and you talk to the actors and you read the screenplay and rehearse and sort of stumble your way through and pick up little pieces. You do your own back-story with some of the stuff that’s on the page as you’ve been told and you fill in the blanks with some of the stuff you make up in your mind. I told the writers, ‘You have to have a good reason for why I left and haven’t seen them in 15 years.’ You have to bring in the Jaws of Life to extract me from the lives of my children. There better be a damn good reason ‘ there’s no reason that’s good enough why he hasn’t been around for 15 years. But they better come up with something that doesn’t make this guy look highly unfavorable.

Release: How many episodes will you be in this season?

BB: I did a month on the show where I shot three episodes in February.

Release: Will you be back next season?

BB: The way my arc ends is a water-cooler moment that leaves it to the eye of the beholder as to whether I’ll be back or not. Nothing’s definitive but I’m certainly hoping they’ll have me back.

Release: It’s been said that you didn’t want to meet Blake Lively prior to filming the scene so that what translated on screen was this relationship of estrangement. Is this true?

BB: I thought it would be interesting to have her, you know, if you put yourself in that situation where you haven’t seen your father in 15 years and all of the sudden you walk into your apartment and he’s standing there in the middle of your living room. It makes life a little bit easier for the actor to sort of recreate the emotional circumstances. I called Kelly ahead of time and said, ‘Let’s talk on the phone and I’ll come to New York a couple of days early from California and let’s grab some lunch,’ because I wanted to get to know her better so we could establish on-screen that we understood one another’s rhythm and tempo. I wanted to have her feel comfortable enough with me, and me comfortable enough with her, that you would believe that we had had a marriage and a meaningful relationship with one another. With Blake I thought it was more interesting to preserve the fact that we hadn’t seen each other and I was interested in having us reunited for the first time when the cameras were rolling.

Release: In the editorial advertisements you and Blake Lively are arm-in-arm and the tagline reads, ‘Daddy’s back and they’ve made up ‘ everything.’ Is your character back with ulterior motives?

BB: [Laughs] Well that’s going to play itself out. Obviously interpret that however you will, but it’s suggesting that if I’m up to no good, she may be complicit. We may sort of both be up to no good. She loves her dad and she’s so thrilled to have him back in her life and doesn’t want to do anything that’ll have him run off again. She wants her father to stay in her life.